While the present invention can be used for any suitable system to handle different size sheets, for clarity, it will be described in relation to use in a xerographic marking apparatus. Any suitable media can be used such as sheet materials, papers, etc. The term “cards” will be used and intended to be inclusive of any sheet media of different lengths.
In an electrostatographic reproducing apparatus commonly used today, a photoconductive insulating member may be charged to a negative potential, thereafter exposed to a light image of an original document to be reproduced. The exposure discharges the photoconductive insulating surface in exposed or background areas and creates an electrostatic latent image on the member which corresponds to the image areas contained within the original document. Subsequently, the electrostatic latent image on the photoconductive insulating surface is made visible by developing the image with a developing powder referred to in the art as toner. During development, the toner particles are attracted from the carrier particles by the charge pattern of the image areas on the photoconductive insulating area to form a powder image on the photoconductive insulating area. This image may be subsequently transferred or marked onto a support surface such as copy paper to which it may be permanently affixed by heating or by the application of pressure. Following transfer of the toner image or marking, the copy paper may be removed from the system by a user or may be automatically forwarded to a finishing station where the copies may be collected, compiled and stapled and formed into books, pamphlets or other sets to be wrapped, etc.
As above noted, there are many marking systems that transport paper or other media after the paper is marked in marking step or steps. These marking systems could include electrostatic marking systems, non-electrostatic marking systems and printers or any other system where paper or other flexible media or receiving sheets are transported internally to an output device such as a finisher and compiler station or stations. These devices include those used for collecting or gathering printed sheets so they may be formed into sets such as books, pamphlets, forms, sales literature, instruction books and manuals and the like.
These electrostatic marking systems have finisher and compilers located at a site after the receiving sheets (paper) have been marked with a toner.
Multi-sheet collations when transported by a pusher belt system after marking either arrive to the belt unregistered are added unregistered to a pre-registered set or become unregistered during transport. Single and multi-sheet collations of different lengths are contained in the process direction by pushers but the length differences in the collations do not allow for side to side registration with fixed registration walls designed to accommodate the largest size. This causes misregistration in those stacks made up of any media with sizes smaller than the registration wall width dimensions.